<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
    <style>
      div {
        width: 80px;
      }

      input[type='text'] {
        width: 50px;
        height: 44px;
        outline: none;
        border: 1px solid #ccc;
        text-align: center;
        border-right: 0;
      }

      input[type='button'] {
        height: 24px;
        width: 22px;
        cursor: pointer;
      }

      input {
        float: left;
        border: 1px solid #ccc;
      }
    </style>
  </head>

  <body>
    <div>
      <input type="text" id="total" value="1" readonly />
      <input type="button" value="+" id="add" />
      <input type="button" value="-" id="reduce" disabled />
      <script></script>
    </div>
  </body>
  <script>
    const total = document.querySelector('#total')
    const add = document.querySelector('#add')
    const reduce = document.querySelector('#reduce')
    add.addEventListener('click',function(){
      
      reduce.disabled=false
      let a=total.value++
      if(a===10){
        add.disabled=true
      }
      
      
      
    })
    reduce.addEventListener('click',function(){
      
      reduce.disabled=false
     
      let b=total.value--
 
      
      console.log(b);
      if(b<1){
        reduce.disabled=true
      }
      
    })
  </script>
</html>
